Peripapillary Retinoschisis in Glaucoma: Association With Progression and OCT Signs of Müller Cell Involvement

Peripapillary fluid: Obvious and not so obvious!

Intraretinal or subretinal fluid in the peripapillary area can be clinically visualized in conditions such as peripapillary choroidal neovascularization, optic disc pit maculopathy, and optic nerve head tumors and granulomas. Optical coherence tomography (OCT) helps to visualize peripapillary fluid in many other chorioretinal conditions such as peripapillary pachychoroid syndrome, posterior uveitis, central retinal vein occlusion, malignant hypertension, hypotonic maculopathy as well as neuro-ophthalmological conditions such as glaucoma, microcystic macular edema and disc edema due papilledema, non-arteritic anterior ischemic optic neuropathy, neuroretinitis, and diabetic papillopathy. Often, the differential diagnosis of peripapillary fluid is a bit tricky and may lead to misdiagnosis and improper management. We describe a diagnostic algorithm for peripapillary fluid on OCT and outline the salient features and management of these conditions.

Association of Bergmeister Papilla and Deep Optic Nerve Head Structures With Prelaminar Schisis of Normal and Glaucomatous Eyes

PURPOSE

To investigate factors associated with the severity of prelaminar schisis (PLS) in heathy subjects and glaucoma patients.

DESIGN

Prospective cross-sectional study.

METHODS

A total of 217 eyes of 217 subjects (110 normal eyes and 107 open angle glaucoma eyes) were studied. Frequency and severity of PLS were compared between normal and glaucomatous eyes. Multivariate logistic models were used to assess factors associated with the severity of PLS. Factors considered were age, axial length, glaucomatous damage indices, Bruch membrane opening (BMO) and anterior scleral canal opening parameters, tractional forces (posterior vitreous staging and presence of Bergmeister papilla), circumpapillary choroidal thickness, lamina cribrosa (LC) parameters, and peripapillary scleral (PPS) angle.

RESULTS

The frequency of PLS was 70.9% in normal eyes and 72.0% in glaucomatous eyes. There was no difference in frequency and severity between the groups. The presence of Bergmeister papilla was the strongest predictor of a more severe PLS in both normal and glaucomatous eyes (odds ratio [OR] + 9.78, 12.5; both P < .001). A larger PPS angle in normal eyes (OR = 1.19; P = .003) and a larger BMO area and a deeper LC depth in glaucomatous eyes (OR = 1.08, 1.05; both P = .038) were associated with severity of PLS.

CONCLUSIONS

The severity of PLS was strongly associated with the presence of Bergmeister papilla, suggesting a traction-related phenomenon. Correlation of PLS severity with larger BMO area and deeper LC depth, which are optic nerve head structures associated with glaucoma, suggested its possible relationship with glaucomatous damage.

Impact of peripapillary retinoschisis on visual field test results in glaucomatous eyes

BACKGROUND/AIMS

To investigate the influence of peripapillary retinoschisis (PRS) on visual field (VF) test results in patients with primary open angle glaucoma (POAG).

METHODS

Thirty eyes of 30 patients with POAG who had PRS at least once were included. All eyes were followed-up for a minimum 5 years at 4-6-month intervals. The occurrence of PRS was determined by circumpapillary retinal nerve fibre layer B-scan on spectral-domain optical coherence tomography (OCT). The global and regional VF deviations just prior to and immediately after PRS formation, or just prior to and immediately after PRS resolution (if it occurred), were compared. VF sensitivity within the region corresponding to the OCT sector where PRS occurred was determined according to the Garway-Heath map.

RESULTS

Global MD (p=0.345) and regional VF deviations (p=0.255) did not differ significantly between immediately after and just prior to PRS formation. Global MD (p=0.846) and regional VF deviations (p=0.758) were also similar between immediately after and just prior to PRS resolution.

CONCLUSION

PRS has no short-term effect on the VF sensitivity. Therefore, VF test can still be useful for evaluating glaucomatous damage even in the presence of PRS compared with OCT.

Optic Nerve Head Abnormalities in Nonpathologic High Myopia and the Relationship With Visual Field

PURPOSE

To describe the optic nerve head (ONH) abnormalities in nonpathologic highly myopic eyes based on swept-source optical coherence tomography (OCT) and the relationship with visual field (VF).

DESIGN

Secondary analysis from a longitudinal cohort study.

METHODS

Highly myopic patients without myopic maculopathy of category 2 or higher were enrolled. All participants underwent a swept-source OCT examination focused on ONH. We differentiated between 3 major types (optic disc morphologic abnormality, papillary/peripapillary tissue defect, and papillary/peripapillary schisis) and 12 subtypes of ONH abnormalities. The prevalence and characteristics of ONH abnormalities and the relationship with VF were analyzed.

RESULTS

A total of 857 participants (1389 eyes) were included. Among the 1389 eyes, 91.86%, 68.61%, and 34.92% of them had at least 1, 2, or 3 ONH abnormalities, respectively, which corresponded to 29.55%, 31.79%, and 35.67% of VF defects, respectively. Among the 12 subtypes of the 3 major types, peripapillary hyperreflective ovoid mass-like structure, visible retrobulbar subarachnoid space, and prelaminar schisis were the most common, respectively. Perimetric defects corresponding to OCT abnormalities were more commonly found in eyes with peripapillary retinal detachment, peripapillary retinoschisis, and peripapillary hyperreflective ovoid mass-like structure. Glaucoma-like VF defects were more common in eyes with deep optic cups (28.17%) and with optic disc pit/pit-like change (18.92%).

CONCLUSIONS

We observed and clarified the ONH structural abnormalities in eyes with nonpathologic high myopia. These descriptions may be helpful to differentiate changes in pathologic high myopia or glaucoma.

Severe macular complications in glaucoma: high-resolution multimodal imaging characteristics and review of the literature

PURPOSE

To describe imaging characteristics of severe macular complications occurring in glaucoma and discuss available treatments.

METHODS

Retrospective case series of glaucomatous patients with macular retinoschisis (MR) and/or serous retinal detachment (SRD). Patients underwent a complete ophthalmological examination and multimodal imaging including retinography, SD-OCT, fluorescein and indocyanine green angiography (FA & ICGA) and adaptive optics (AO).

RESULTS

Ten eyes (8 patients) were included. Initial BCVA was 1.04 ± 1.12 logMAR and IOP was 24.0 ± 9.3mmHg. All eyes presented with MR while SRD was present in 5 eyes (5 patients), with a central macular thickness of 573 ± 152 μm. FA and ICGA allowed to exclude leakage in all cases. A focal lamina cribrosa defect (LCD) was found in four eyes (4 patients) using OCT, with AO providing en-face visualization of the defect in one eye. Outer retinal hole was present in 3 eyes (3 patients). No visual improvement or resolution of the macular retinoschisis was observed in eyes with medical or surgical IOP control (N = 9). Vitrectomy with internal membrane limiting peeling and gas tamponade was performed in one eye with good visual results.

CONCLUSIONS

Multimodal high-resolution imaging is essential to diagnose severe macular complications associated with advanced glaucoma.

Glaucomatous optic nerve damage in the contralateral eye of a patient with peripapillary retinoschisis: a case report

BACKGROUND

Peripapillary retinoschisis (PPRS) is often associated with glaucomatous eyes. It usually occurs in eyes with a more advanced stage of glaucoma with obvious optic nerve damage. We report a patient who was found to have PPRS in one eye during a routine physical examination without obvious glaucoma symptoms. Further examination revealed glaucomatous visual field loss and retinal nerve fiber layer defects in the contralateral eye.

CASE PRESENTATION

A 55-year-old man presented for a routine physical examination. The anterior segment was normal in both eyes. Fundus examination revealed an elevated and red optic disc in the right eye. In addition, scattered patchy red lesions were seen on the retina on the temporal side of the optic disc. The color and boundary of the left optic disc were normal, and the cup-to-disc ratio was 0.6. Optical coherence tomography showed retinoschisis on the optic nerve head of the right eye throughout the entire circumference, extending to the retina on the temporal side of the optic disc. The intraocular pressure was 18 mmHg OD and 19 mmHg OS. The patient was diagnosed with PPRS (OD). However, no optic disc pit or optic disc coloboma was found. Further examination showed that the visual field of the patient's right eye was generally normal, while a glaucomatous visual field defect was found in the left eye, which manifested as a nasal step visual field defect. Moreover, stereophotography and a red-free fundus image revealed two retinal nerve fiber layer defects in the supratemporal and infratemporal regions of the retina of the left eye. Continuous intraocular pressure measurement found that the intraocular pressure fluctuated between 18 and 22 mmHg OD and 19-26 mmHg OS during the daytime. Primary open-angle glaucoma was then diagnosed.

CONCLUSIONS

In this case, we found that PPRS was associated with glaucomatous optic nerve changes and visual field defects in the fellow eye.

Clinical characteristics and risk factors of myopic retinoschisis in an elderly high myopia population

PURPOSE

To investigate the clinical characteristics, internal correlations and risk factors for different locations of retinoschisis (RS) in an elderly high myopia (HM) population.

METHODS

A total of 448 eyes (304 participants) were analysed and classified into no retinoschisis (no-RS), paravascular retinoschisis (PVRS), peripapillary retinoschisis (PPRS) and macular retinoschisis (MRS) groups. Each participant underwent comprehensive ophthalmic examinations, and posterior scleral height (PSH) was measured in swept-source optical coherence tomography images. PSH, vitreoretinal interface abnormities and myopic atrophy maculopathy (MAM) were compared among groups.

RESULTS

Retinoschisis was found in 195 (43.5%) eyes, among which 170 (37.9%) had PVRS, 123 (27.5%) had PPRS, and 103 (23.0%) had MRS. MRS was found to be combined with PVRS in 96 of 103 (93.2%) eyes. MAM was one of the risk factors for RS (odds ratio [OR], 2.459; p = 0.005). Higher nasal PSH was the only risk factor for PVRS (OR, 9.103; p = 0.008 per 1-mm increase). Elongation of axial length (AL) (OR, 1.891; p < 0.001 per 1-mm increase), higher PSH in nasal (OR, 5.059; p = 0.009 per 1-mm increase) and temporal (OR, 13.021; p = 0.012 per 1-mm increase), epiretinal membrane (ERM; OR, 2.841; p = 0.008) and vitreomacular traction (VMT; OR, 7.335; p = 0.002) were risk factors for MRS.

CONCLUSIONS

Paravascular retinoschisis is the most common type of RS in HM and MRS is mostly combined with PVRS. MAM is one of the risk factors for RS. In addition to longer AL and higher PSH, the presence of VMT and ERM also play an important role in the formation of MRS.

Astrocyte Immune Functions and Glaucoma

Astrocytes, a non-neuronal glial cell type in the nervous system, are essential for regulating physiological functions of the central nervous system. In various injuries and diseases of the central nervous system, astrocytes often change their phenotypes into neurotoxic ones that participate in pro-inflammatory responses (hereafter referred to as "immune functions"). Such astrocytic immune functions are not only limited to brain diseases but are also found in ocular neurodegenerative diseases such as glaucoma, a retinal neurodegenerative disease that is the leading cause of blindness worldwide. The eye has two astrocyte-lineage cells: astrocytes and Müller cells. They maintain the physiological environment of the retina and optic nerve, thereby controlling visual function. Dysfunction of astrocyte-lineage cells may be involved in the onset and progression of glaucoma. These cells become reactive in glaucoma patients, and animal studies have suggested that their immune responses may be linked to glaucoma-related events: tissue remodeling, neuronal death, and infiltration of peripheral immune cells. In this review, we discuss the role of the immune functions of astrocyte-lineage cells in the pathogenesis of glaucoma.

Peripapillary Retinoschisis as a Manifestation of Ocular Hypotony

The aim of this case report was to present an unusual case of peripapillary retinoschisis (PPRS) associated with ocular hypotony after glaucoma surgery. It refers to a 78-year-old man with primary open-angle glaucoma who developed PPRS while hypotonous. Optical coherence tomography of the peripapillary and the macular area of the right eye revealed PPRS temporally and nasally to the optic disc, more prominent at the level of the outer nuclear layer and less so at the inner nuclear layer. The PPRS completely regressed after 1 month of treatment and restoration of intraocular pressure to normal levels. This case report highlights the fact that PPRS in glaucoma patients may present in the setting of ocular hypotony and appears to resolve when the hypotony is successfully managed. Hydrostatic pressure gradient across retinal vasculature that allows movement of fluid into the extracellular spaces is a potential mechanism for the development of PPRS in ocular hypotony.

Hypodense regions in the peripapillary region increased the risk of macular retinoschisis detected by optical coherence tomography

Purpose

The purpose of the present study was to investigate the clinical features of peripapillary regions in patients with myopic macular retinoschisis (MRS) and its association with the development of retinoschisis (RS).

Methods

In this cross-sectional study, high-myopic patients with or without MRS were recruited, and the hypodense regions were analyzed in the peripapillary regions. The vitreoretinal adhesions around both macular and paravascular arcades were compared between groups. The risk factors for the development of MRS were analyzed by logistic regression.

Results

Of 88 myopic eyes, MRS was detected in 45 eyes (51%). The eyes with MRS showed a higher rate of peripapillary and paravascular retinoschisis (P &lt; 0.001 and P = 0.006). Hypodense regions were detected in 25 eyes (20.35%). Higher rates of horizontal and vertical macular MRS were detected in the hypodense group (P = 0.012 and P = 0.002). Lower refractive error, longer axial length, and higher rates of outer retinoschisis both in horizontal and vertical macular regions were observed in the hypodense group (P = 0.012, P = 0.006, P = 0.038, and P = 0.034). Higher rates of inner and outer retinoschisis, vitreoschisis, and microfolds along superior vascular arcade were detected in the hypodense group (P = 0.005, P = 0.001, P = 0.014, and P = 0.014). Higher rates of internal limiting membrane (ILM) detachment, inner and outer RS were detected along the inferior vascular arcade in the hypodense group (P = 0.008, P = 0.001, and P = 0.028). Hypodense regions, the axial length and PICC (peripapillary intrachoroidal cavitation) were significantly correlated with the severity of MRS (Odds ratio = 0.207, P = 0.010; Odds ratio = 1.399, P = 0.016; Odds ratio = 0.142, P = 0.010).

Conclusions

The hypodense regions were likely to affect outer retinoschisis both in macular and paravascular regions. It was a risk factor for the development of MRS.

Optic nerve cavitations in glaucoma suspect and glaucoma patients

Purpose

Glaucoma is associated with structural changes of the optic nerve head such as deformation, lamina cribosa defects, prelaminar schisis, and peripapillary retinal schisis. We describe optic nerve cavitations that were detected by routine spectral domain optical coherence tomography (OCT).

Observations

OCT imaging showed cavitations in 5 eyes of 4 patients with an initial diagnosis of glaucoma or glaucoma suspect. The cavitations were seen as hyporeflective spaces that are sharply delineated from surrounding tissue. They were centered inferonasally, anterior to the lamina cribosa, and at least partially within the Bruch's membrane opening (BMO). They extended from 3 to 6 clock hours.

Conclusion

AND IMPORTANCE: We describe a new OCT finding in patients with a diagnosis of glaucoma and glaucoma suspect. While previous reports describe cavitations in the choroid in patients with pathological myopia, our patients had minimal refractive error and the cavitations were located within the optic nerve. We will examine these patients over time to determine the impact of this finding on longitudinal changes in structure and function.

Clinicians' Use of Quantitative Information When Assessing the Rate of Structural Progression in Glaucoma

PURPOSE

OCT scans contain large amounts of information, but clinicians often rely on reported layer thicknesses when assessing the rate of glaucomatous progression. We sought to determine which of these quantifications most closely relate to the subjective assessment of glaucoma experts who had all the diagnostic information available.

DESIGN

Prospective cohort study.

PARTICIPANTS

Eleven glaucoma specialists independently scored the rate of structural progression from a series of 5 biannual clinical OCT printouts.

METHODS

A total of 100 glaucoma or glaucoma suspect eyes of 51 participants were included; 20 were scored twice to assess repeatability. Scores ranged from 1 (improvement) to 7 (very rapid progression). Generalized estimating equation linear models were used to predict the mean clinician score from the rates of change of retinal nerve fiber layer thickness (RNFLT) or minimum rim width (MRW) globally or in the most rapidly thinning of the 6 sectors.

MAIN OUTCOME MEASURES

The correlation between the objective rates of change and the average of the 11 clinicians' scores.

RESULTS

Average RNFLT within the series of study eyes was 79.3 μm (range, 41.4-126.6). Some 95% of individual clinician scores varied by ≤ 1 point when repeated. The mean clinician score was more strongly correlated with the rate of change of RNFLT in the most rapidly changing sector in %/year (pseudo-R2 = 0.657) than the rate of global RNFLT (0.372). The rate of MRW in the most rapidly changing sector had pseudo-R2 = 0.149.

CONCLUSIONS

The rate of change of RNFLT in the most rapidly changing sector predicted experts' assessment of the rate of structural progression better than global rates or MRW. Sectoral rates may be a useful addition to current clinical printouts.

Non-vasogenic cystoid maculopathies

Besides cystoid macular edema due to a blood-retinal barrier breakdown, another type of macular cystoid spaces referred to as non-vasogenic cystoid maculopathies (NVCM) may be detected on optical coherence tomography but not on fluorescein angiography. Various causes may disrupt retinal cell cohesion or impair retinal pigment epithelium (RPE) and Müller cell functions in the maintenance of retinal dehydration, resulting in cystoid spaces formation. Tractional causes include vitreomacular traction, epiretinal membranes and myopic foveoschisis. Surgical treatment does not always allow cystoid space resorption. In inherited retinal dystrophies, cystoid spaces may be part of the disease as in X-linked retinoschisis or enhanced S-cone syndrome, or occur occasionally as in bestrophinopathies, retinitis pigmentosa and allied diseases, congenital microphthalmia, choroideremia, gyrate atrophy and Bietti crystalline dystrophy. In macular telangiectasia type 2, cystoid spaces and cavitations do not depend on the fluid leakage from telangiectasia. Various causes affecting RPE function may result in NVCM such as chronic central serous chorioretinopathy and paraneoplastic syndromes. Non-exudative age macular degeneration may also be complicated by intraretinal cystoid spaces in the absence of fluorescein leakage. In these diseases, cystoid spaces occur in a context of retinal cell loss. Various causes of optic atrophy, including open-angle glaucoma, result in microcystoid spaces in the inner nuclear layer due to a retrograde transsynaptic degeneration. Lastly, drug toxicity may also induce cystoid maculopathy. Identifying NVCM on multimodal imaging, including fluorescein angiography if needed, allows guiding the diagnosis of the causative disease and choosing adequate treatment when available.

Molecular regulation of neuroinflammation in glaucoma: Current knowledge and the ongoing search for new treatment targets

Neuroinflammation relying on the inflammatory responses of glial cells has emerged as an impactful component of the multifactorial etiology of neurodegeneration in glaucoma. It has become increasingly evident that despite early adaptive and reparative features of glial responses, prolonged reactivity of the resident glia, along with the peripheral immune cells, create widespread toxicity to retinal ganglion cell (RGC) axons, somas, and synapses. As much as the synchronized responses of astrocytes and microglia to glaucoma-related stress or neuron injury, their bi-directional interactions are critical to build and amplify neuroinflammation and to dictate the neurodegenerative outcome. Although distinct molecular programs regulate somatic and axonal degeneration in glaucoma, inhibition of neurodegenerative inflammation can provide a broadly beneficial treatment strategy to rescue RGC integrity and function. Since inflammatory toxicity and mitochondrial dysfunction are converging etiological paths that can boost each other and feed into a vicious cycle, anti-inflammatory treatments may also offer a multi-target potential. This review presents an overview of the current knowledge on neuroinflammation in glaucoma with particular emphasis on the cell-intrinsic and cell-extrinsic factors involved in the reciprocal regulation of glial responses, the interdependence between inflammatory and mitochondrial routes of neurodegeneration, and the research aspects inspiring for prospective immunomodulatory treatments. With the advent of powerful technologies, ongoing research on molecular and functional characteristics of glial responses is expected to accumulate more comprehensive and complementary information and to rapidly move the field forward to safe and effective modulation of the glial pro-inflammatory activities, while restoring or augmenting the glial immune-regulatory and neurosupport functions.

Clinical Features of Advanced Glaucoma With Optic Nerve Head Prelaminar Schisis

PURPOSE

To investigate the clinical characteristics of optic nerve head (ONH) prelaminar schisis in eyes with advanced glaucoma.

DESIGN

Cross-sectional study.

METHODS

One hundred sixteen eyes with advanced glaucoma (30-2 mean deviation <-12 dB) were included. ONH prelaminar schisis was identified using the spectral-domain optical coherence tomography independently by 2 evaluators and only eyes that reached consensus for the presence of ONH prelaminar schisis were included. Bruch membrane opening-minimum rim width (BMO-MRW), thickness and depth of lamina cribrosa (LC), peripapillary retinal nerve fiber layer (RNFL) thickness, macular thickness (total, RNFL, ganglion cell layer, inner plexiform layer), and peripapillary and subfoveal choroidal thickness were additionally obtained. Clinical characteristics were compared between the 2 groups based on the presence of ONH prelaminar schisis.

RESULTS

ONH prelaminar schisis was identified in 48 of 116 eyes. Multivariate logistic regression analysis revealed that short axial length, thin and deep LC, and thick macula were associated with the presence of ONH prelaminar schisis. When the structure-function relationships were determined, macular structural parameters tended to have a better relationship with functional parameters than the BMO-MRW and peripapillary RNFL thickness parameters in eyes with ONH prelaminar schisis.

CONCLUSIONS

The ONH prelaminar schisis was associated with thin and deep LC, short axial length, and generally thick macula. In patients with this features, the macular measurements, rather than peripapillary or ONH measurements, better predict the functional status of the eye. Our findings may have significant clinical implications for management of advanced glaucoma eyes with and without ONH prelaminar schisis.

AN ASSOCIATION BETWEEN STELLATE NONHEREDITARY IDIOPATHIC FOVEOMACULAR RETINOSCHISIS, PERIPHERAL RETINOSCHISIS, AND POSTERIOR HYALOID ATTACHMENT

PURPOSE

Stellate nonhereditary idiopathic foveomacular retinoschisis is a disorder characterized by splitting of the retina at the macula, without a known underlying mechanical or inherited cause. This study investigates demographic, anatomical, and functional characteristics of subjects with stellate nonhereditary idiopathic foveomacular retinoschisis, to explore potential underlying mechanisms.

METHODS

In this single-site, retrospective, and cross-sectional, observational study, data were collected from 28 eyes from 24 subjects with stellate nonhereditary idiopathic foveomacular retinoschisis. Descriptive statistics were reported, based on the observed anatomico-functional features.

RESULTS

The visual acuity remained stable (median 20/20) in all subjects over a median follow-up of 17 months. All cases demonstrated foveomacular retinoschisis within Henle's fiber layer, at the junction of the outer plexiform and outer nuclear layers. This schisis cavity extended beyond the limits of the macular OCT temporally in all eyes. In most affected eyes, there were documented features of peripheral retinoschisis and broad attachment of the posterior hyaloid at the macula. Functional testing in a cross-sectional subset demonstrated normal retinal sensitivity centrally but an absolute scotoma peripherally.

CONCLUSION

Stellate nonhereditary idiopathic foveomacular retinoschisis seems to be associated with peripheral retinoschisis and anomalous or incomplete posterior hyaloid detachment. Despite chronic manifestation, this does not significantly affect central visual function but can manifest with profound loss of peripheral visual function.

The Progression of Peripapillary Retinoschisis May Indicate the Progression of Glaucoma

Purpose

To identify the temporal correlation between the increase in peripapillary retinoschisis (PPRS) and glaucoma progression during PPRS fluctuation.

Methods

We performed a comparative clinical timeline analysis for PPRS and glaucomatous progression in eyes with PPRS. In particular, the interval between the increase in PPRS extent and glaucoma progression was analyzed. Temporal correlation was defined when the interval was less than one year between glaucoma progression and PPRS increase, including both de novo development and an increase in the amount of retinoschisis on serial optical coherence tomography.

Results

We included 33 eyes of 30 patients, with an average follow-up period of 7.5 ± 3.0 years and a total of 253 glaucoma examinations. Glaucoma progression was observed in 21 of 33 eyes; 19 (90.5%) of the 21 eyes with glaucoma progression and 29 (74.4%) of the 39 episodes of PPRS increase showed temporal correlation. The de novo development of PPRS during the follow-up period over baseline PPRS was more frequently observed in the glaucoma progression group than in the no-progression group (P = 0.006).

Conclusions

In glaucomatous eyes with PPRS, the increase in PPRS temporally correlated with glaucoma progression. Possible glaucoma progression may be considered around the time of increase and de novo development of PPRS.

Foveal regeneration after resolution of cystoid macular edema without and with internal limiting membrane detachment: presumed role of glial cells for foveal structure stabilization

AIM

To document with spectral-domain optical coherence tomography the morphological regeneration of the fovea after resolution of cystoid macular edema (CME) without and with internal limiting membrane (ILM) detachment and to discuss the presumed role of the glial scaffold for foveal structure stabilization.

METHODS

A retrospective case series of 38 eyes of 35 patients is described. Of these, 17 eyes of 16 patients displayed foveal regeneration after resolution of CME, and 6 eyes of 6 patients displayed CME with ILM detachment. Eleven eyes of 9 patients displayed other kinds of foveal and retinal disorders associated with ILM detachment.

RESULTS

The pattern of edematous cyst distribution, with or without a large cyst in the foveola and preferred location of cysts in the inner nuclear layer or Henle fiber layer (HFL), may vary between different eyes with CME or in one eye during different CME episodes. Large cysts in the foveola may be associated with a tractional elevation of the inner foveal layers and the formation of a foveoschisis in the HFL. Edematous cysts are usually not formed in the ganglion cell layer. Eyes with CME and ILM detachment display a schisis between the detached ILM and nerve fiber layer (NFL) which is traversed by Müller cell trunks. ILM detachment was also found in single eyes with myopic traction maculopathy, macular pucker, full-thickness macular holes, outer lamellar holes, and glaucomatous parapapillary retinoschisis, and in 3 eyes with Müller cell sheen dystrophy (MCSD). As observed in eyes with MCSD, cellophane maculopathy, and macular pucker, respectively, fundus light reflections can be caused by different highly reflective membranes or layers: the thickened and tightened ILM which may or may not be detached from the NFL, the NFL, or idiopathic epiretinal membranes. In eyes with short single or multiple CME episodes, the central fovea regenerated either completely, which included the disappearance of irregularities of the photoreceptor layer lines and the reformation of a fovea externa, or with remaining irregularities of the photoreceptor layer lines.

CONCLUSION

The examples of a complete regeneration of the foveal morphology after transient CME show that the fovea may withstand even large tractional deformations and has a conspicuous capacity of structural regeneration as long as no cell degeneration occurs. It is suggested that the regenerative capacity depends on the integrity of the threedimensional glial scaffold for foveal structure stabilization composed of Müller cell and astrocyte processes. The glial scaffold may also maintain the retinal structure after loss of most retinal neurons as in late-stage MCSD.

Disc hemorrhage following peripapillary retinoschisis in glaucoma: a case report

BACKGROUND

Disc hemorrhage (DH) is an important factor often associated with the development and especially progression of glaucoma. In contrast, some studies have reported peripapillary retinoschisis in glaucoma, but it is not recognized as a pathognomonic finding, and opinions on the clinical significance of retinoschisis are not consistent. Here,we present the case of DH following peripapillary retinoschisis in the same area within the same glaucomatous eye.

CASE PRESENTATION

A 70-year-old man with high intraocular pressure (IOP) was referred to the glaucoma clinic. At the time of the baseline study, the IOP was 30mmHg, and peripapillary retinoschisis was discovered at 7 o'clock on the periphery of the optic nerve with swept-source optical coherence tomography. Accompanying retinal nerve fiber layer defect were manifest in the inferotemporal part with red-free fundus photography. Under the impression of open-angle glaucoma, we prescribe latanoprost ophthalmic solution. Eight months later, the IOP was 17mmHg, and the peripapillary retinoschisis had disappeared. DH was observed in the inferotemporal area in the same direction as that of the previous peripapillary retinoschisis.

CONCLUSIONS

The case presented here are the first to report on the relationship between peripapillary retinoschisis and DH. Hopefully future studies will reveal the actual connection between peripapillary retinoschisis and DH.

Factors Determining the Morphology of Peripapillary Retinoschisis

Purpose

We conducted cross-sectional examinations to determine the frequency of peripapillary retinoschisis (PRS) in eyes with glaucoma and suspected glaucoma and analyzed the pathogenesis of PRS by using spectral-domain optical coherence tomography (SD-OCT).

Patients and Methods

In 1516 cases involving glaucoma and suspected glaucoma, we retrospectively reviewed the disc and macular volume scans obtained by SD-OCT and categorized PRS into two groups based on whether the retinoschisis was closer to the optic nerve over the Bruch’s membrane opening (BMO) (ahead group) or did not go past the BMO (behind group) and then compared the characteristics between both groups.

Results

The total frequency of PRS was 1.49% (20/1342 eyes) in primary open-angle glaucoma (POAG) eyes and 0.59% (10/1687 eyes) in glaucoma suspects. In the behind group, PRS was mostly detected in the inner layers of the retina (retinal nerve fiber layer: 30.9%, ganglion cell layer: 21.8%, inner plexiform layer: 7.3%). However, in the ahead group, PRS was detected in the outer layers (inner nuclear layer: 10%, outer plexiform layer: 20%, outer nuclear layer: 50%). In addition, the eyes in the ahead group had significantly greater axial lengths and significantly smaller spherical equivalent values. These two differences suggest that the pulling force of the vitreous traction may play an important role in PRS only in the behind group and that the scleral stretching force may play a role in the development of PRS in the ahead group.

Conclusion

The frequency of PRS in patients with POAG is higher than that in patients with suspected glaucoma. Both forms of PRS are affected by posterior vitreous detachment and axial length elongation. Careful follow-up is required to assess the development of PRS in glaucoma suspects. The pathogenesis of PRS has been elucidated to some degree by classifying the morphological condition of the PRS and BMO.

Evidence-based understanding of disc hemorrhage in glaucoma

Disc hemorrhage is a characteristic finding that is highly associated with glaucoma development or progression. Consequently, the literature commonly designates disc hemorrhage as a "risk factor" for glaucoma progression; however, the exact cause-and-effect relationship or mechanism remains unclear. In this review, we discuss the emerging evidence that disc hemorrhage is a secondary development that follows glaucomatous damage. As our understanding of disc hemorrhage has progressed in recent decades, we suggest the terminology be changed from "risk factor" to "indicator" of ongoing glaucomatous development or progression for a more accurate description, better indication of the clinical implications and, ultimately, a better guide for future research.

Case Report: Glaucoma-associated Peripapillary Retinoschisis with Corresponding Lamina Cribrosa Defect

SIGNIFICANCE

Peripapillary retinoschisis is associated with primary and secondary glaucoma. It is important that clinicians are familiar with the presentation and management of peripapillary retinoschisis to understand its effects on the patient's glaucoma and to avoid unnecessary referral when the macula is not involved.

PURPOSE

We present a case of peripapillary retinoschisis found incidentally on routine optical coherence tomographic (OCT) surveillance of primary open-angle glaucoma.

CASE REPORT

A 70-year-old man presented for his annual diabetic eye examination. Surveillance with OCT revealed a splitting of the inner peripapillary retina corresponding to a previously noted notch in the right optic nerve. Further imaging of the right eye using enhanced depth imaging OCT revealed a defect in the lamina cribrosa that may have contributed to the formation and persistence of peripapillary retinoschisis. Retinal nerve fiber layer analysis showed a 5-year history of progressive temporal and inferotemporal thickening in the right eye. The patient was managed conservatively with instruction on regular Amsler grid testing.

CONCLUSIONS

As seen in this case, peripapillary retinoschisis typically alters retinal nerve fiber layer thickness on OCT and can be mistakenly attributed to glaucomatous change. Glaucoma-associated peripapillary retinoschisis is usually not vision threatening and can be managed conservatively; in rare cases of progression to macular involvement, patients should be referred to a retina specialist.

Vitrectomy with peripapillary internal limiting membrane peeling for macular retinoschisis associated with normal-tension glaucoma

Purpose

Although vitrectomy has been reported to be effective for the treatment of macular retinoschisis associated with glaucoma in a few case series, the surgical techniques have yet to be established. This article aimed to describe the cases of two patients with macular retinoschisis who underwent vitrectomy with peripapillary internal limiting membrane peeling around the defective area of the retinal nerve fiber layer.

Observations

Both patients had been diagnosed with normal tension glaucoma and treated with eye drops to stabilize intraocular pressure. Progression of macular retinoschisis and accompanied vision loss were observed in both cases. Twelve months after the surgery, both patients had resolution of the retinoschisis and improvement in best corrected visual acuity.

Conclusions and importance

Our surgical technique may be effective for the resolution of macular retinoschisis in eyes with normal tension glaucoma.

A proposed mechanism influencing structural patterns in X-linked retinoschisis and stellate nonhereditary idiopathic foveomacular retinoschisis

OBJECTIVE

To explore the structural differences between X-linked retinoschisis (XLR) and stellate nonhereditary idiopathic foveomacular retinoschisis (SNIFR) using swept-source optical coherence tomography angiography (SS-OCTA).

METHODS

A case series of two patients, a 9-year-old male with XLR and a 58-year-old woman with SNIFR were imaged with swept-source optical coherence tomography angiography (SS-OCTA; PLEX Elite 900, Carl Zeiss Meditec, Inc, Dublin, CA). Automated segmentation was manually adjusted to include the areas of retinoschisis within en face flow and structural slabs. The flow data were binarized using ImageJ 1.51s (Wayne Rasband, National Institutes of Health, USA, http://imagej.nih.gov.ij ) and superimposed onto the structural slab.

RESULTS

In the eye with XLR, OCTA flow data superimposed on the structural slab demonstrated flow signal within numerous bridging structures connecting the inner and outer plexiform layers containing the intermediate (ICP) and deep (DCP) capillary plexuses. In contrast, the same technique applied to the eye with SNIFR demonstrated an absence of flow signal in the cystic retinal spaces within Henle's fiber layer.

CONCLUSIONS

The vascular pattern of bridging vessels between the ICP and DCP is closely related to the structural "retinoschisis" pattern of XLR and appears to be structurally different from that seen in SNIFR. Moreover, the connecting vessels appear to be highly represented and regularly distributed, thereby supporting a serial arrangement of the retinal capillary plexuses within the perifoveal macula.